The present invention provides a method for transmitting data, a method for receiving data and a device. The transmitting method includes: transmitting, by an STA, characterizing information to an AP, the characterizing information is used to characterize a maximum transmission delay allowed by uplink data to be transmitted by the STA; receiving, by the STA, transmission time that is specified for the STA and returned by the AP within the maximum transmission delay allowed by the uplink data to be transmitted by the STA, wherein the transmission time is within a range of the maximum transmission delay allowed by the uplink data to be transmitted by the STA; and transmitting, by the STA, the uplink data to the AP within the transmission time. Technical solutions of the present invention solve a problem of data transmission in an emergency application scenario, and guarantee requirements placed by emergency data upon transmission delay.